Here's the best I can do for tonight.

Now at 4.4 sigma with

 http://abelian.org/vlf/tmp/170321c.gif

S/N 12.8 dB in 55 uHz.

I dropped out the 15th and 17th, each of these
days make the sum worse.   But dropping any
of the other days reduces the signal.  Therefore
it is repeating each day.

Bearing is definitely east and now there's a bit
more signal it looks like the phase between E/W
loop and E-field is about right.  Not much signal
in the N/S and the phase is funny.  Behaving like
there's some significant elliptic polarisation.

I can't improve the signal by sliding out of the
range 14:00 to 19:00, nor by increasing or reducing
the 5 hour span.

Not yet added today into the stack.
--
Paul Nicholson
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